Scanner with a lateral reversing device

ABSTRACT

A scanner including at least a casing, a scanning platform, a carriage and a lateral reversing device is provided. The scanning platform is installed on the covering panel of the casing and is used to accommodate at least one document. The carriage is movably installed in the casing and will transmit a scan-finished signal after having scanned the front side of a document. The lateral reversing device, which is installed at a lateral side of the scanning platform, is equipped with a control unit and is used to turn the document over for the reverse side of the document to be scanned after the control unit has received the scan-finished signal.

[0001] This application claims the benefit of Taiwan application Serial No. 91122909, filed on Oct. 3, 2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention to a scanner with a lateral reversing device.

[0003] 2. Description of the Related Art

[0004] Please refer to FIG. 1, a three-dimensional structural diagram of a general scanner 100. In FIG. 1, the scanner 100 includes a base 102 and a covering lid 104, wherein the covering lid 104 is installed on the base 102 by bucking one end of the covering lid 104 on one end of the base 102 via a pivotal shaft device 106 so that the covering lid 104 can open from and close to the base 102.

[0005] The base 102 includes a covering panel 108, a scanning platform 110 and a carriage 114, wherein the covering panel 108 is situated on top of the base 102 while the scanning platform 110 on which a document 112 are placed is installed on the covering panel 108. Of which, the carriage 114, which is movably installed in the base 102, can move along the arrow 150 back and forth to scan the document 112 when the covering lid 104 is closed to the base 102.

[0006] When the front side of the document 112 is to be scanned, the user has to, first of all, lift the covering lid 104 manually. Next, the user has to place the document 112 on the scanning platform 110, and the front side of the document 112 is faced downward. Following that, the user shall close the covering lid 104 to the base 102. At last, the user can now start the carriage 114 to scan the front side of the document 112.

[0007] If the reverse side of the document 112 is to be scanned, the user has to, first of all, lift the covering lid 104 manually. Next, the user has to turn the document over 112, and its reverse side is faced downward. Following that, the user shall close the covering lid 104 to the base 102. At last, the user can now start the carriage 114 to scan the reverse side of the document 112. Apart from that, when the carriage 114 is started, the carriage 114 starts to scan from the scan-starting point to the scan-finishing point. The next scanning process cannot be resumed unless the carriage 114 has returned to the scan-starting point again. As a consequence, the user not only has to turn the document over, but also has to wait for the carriage to return to the starting point.

[0008] The recurrent process of alternating the front side with reverse side of a document and the return of the carriage will cause tremendous inconveniences and waste of time to the user when there are a large number of documents to be processed.

SUMMARY OF THE INVENTION

[0009] It is therefore an object of the invention to provide a scanner with a lateral reversing device. The design of installing a lateral reversing device at a lateral side of the scanning platform enables the scanner to overturn the document after the front side has been scanned so the reverse side can be scanned, achieving a double-sided scanning function. The user does not have to turn the document over manually which is indeed very convenient.

[0010] It is therefore an object of the invention to provide a scanner including at least a casing, a scanning platform, a carriage and a lateral reversing device. The scanning platform is installed on the covering panel of the casing and is used to accommodate at least one document. The carriage is movably installed in the casing and will transmit a scan-finished signal after having scanned the front side of a document. The lateral reversing device, which is installed at a lateral side of the scanning platform, is equipped with a control unit and is used to turn the document over for the reverse side of the document to be scanned after the control unit has received the scan-finished signal.

[0011] It is therefore an object of the invention to provide a document double-sided scanning method which is applied to a scanner, wherein the scanner includes a carriage, a scanning platform where at least one document is placed, and a lateral reversing device which is installed at a lateral side of the scanning platform. According to the method, first of all, the carriage scans the front side of the document; next, the lateral reversing device overturns the document after the carriage has scanned the front side of the document; at last, the carriage scans the reverse side of the document.

[0012] Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013]FIG. 1 shows a three-dimensional structural diagram of a conventional scanner;

[0014]FIG. 2 shows a cross-sectional view of a scanner equipped with a lateral reversing device according to a preferred embodiment of the invention;

[0015]FIG. 3 is a schematic diagram for the first roller, the second roller, and the third roller as well as the first shaft, the second shaft, and the third shaft;

[0016]FIG. 4 is a block diagram according to the scanner shown in FIG. 2;

[0017]FIG. 5 shows a cross-sectional diagram of the first roller as shown in FIG. 2 carrying a document moving towards the second roller;

[0018]FIG. 6 shows a cross-sectional diagram of the second roller and the third roller in FIG. 2 carrying a document moving along the gyration orbit;

[0019]FIG. 7 shows a cross-sectional diagram of the document in the gyration orbit shown in FIG. 2 blocking the infrared emitted by the infrared emitter and moving towards the scanning platform when carried by the first roller;

[0020]FIG. 8 is a cross-sectional diagram of the document in FIG. 2 having been overturned and placed on the scanning platform; and

[0021]FIG. 9 is a flowchart illustrating the document double-sided scanning method according to a preferred embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0022] Referring first to FIG. 2, a cross-sectional view of a scanner 200 equipped with a lateral reversing device 220 according to a preferred embodiment of the invention. In FIG. 2, the scanner 200 includes at least a casing 202, a scanning platform 210, a carriage 214, and a lateral reversing device 220 (the area within the dotted line as shown in FIG. 2). The casing 202 is equipped with a covering panel 208 and a lateral panel 209; the scanning platform 210 on which a document 212 is placed is installed on the covering panel 208; moreover, the document 212 has document front side 212 a and document reverse side 212 b.

[0023] The carriage 214, which is movably installed in the casing 202 and is used to scan the document front side 212 a or document reverse side 212 b, outputs a scan-finished signal after having scanned the document front side 212 a. The lateral reversing device 220, which is installed on the covering panel 208 and is situated at a lateral side of the scanning platform 210, overturns the document 212 for document reverse side 212 b to be scanned as soon as document front side 212 a has been scanned by the carriage 214.

[0024] The design of the lateral reversing device 220 according to the invention overturns the document 212 automatically, exempting the user from overturning the document 212 manually which is indeed very convenient.

[0025] The lateral reversing device 220 includes a driving gear 222, a first passive gear 224, a second passive gear 226, a first roller 228, a second roller 230, a third roller 232, a first shaft 242, a second shaft 244, a third shaft 246, a baffle 234, a gyration orbit 238, and a sensing unit. Of which, the sensing unit can be, for example, an infrared emitter 240 a and an infrared receiver 240 b. All of the driving gear 222, the first passive gear 224, and the second passive gear 226 are vertically installed on top of the covering panel 208 and, moreover, are situated at a lateral side of the scanning platform 210. The first passive gear 224 can gear into the driving gear 222 or can be detached from the driving gear 222 in natural state, while the second passive gear 226 gears into the driving gear 222, the first passive gear 224 and the second passive gear 226 are situated to the two sides of the infra-margin of the driving gear 222. Of which, the first passive gear 224 is situated on an edge of the scanning platform 210 while the second passive gear 226 is close to the lateral panel 209.

[0026] As shown in FIG. 3, the two sides of the first roller 228, the second roller 230, and the third roller 232 extend outwardly to form the first shaft 242, the second shaft 244, and the third shaft 246 respectively around which the first roller 228, the second roller 230, and the third roller 232 rotate individually. Furthermore, the first roller 228, the second roller 230, and the third roller 232 are penetrated and fixed by the first shaft 242, the second shaft 244, and the third shaft 246 respectively. The first roller 228 is situated on an edge of the scanning platform 210, while the third roller 232 and the second roller 230, which are installed as a pair on the covering panel 208 in FIG.2, and the third roller 232 is above the second roller 230. Moreover, the extension of the second shaft 244 and the third shaft 246 parallels to the direction of the movement of the carriage 214 as shown in FIG. 2.

[0027] It is noteworthy that one of the two ends of the first shaft 242, the second shaft 244 and the third shaft 246 as shown in FIG. 3 are connected to the axis of the first passive gear 224, the axis of the second passive gear 226 and one end of the movable shaft 236 as shown in FIG. 2 respectively, while the other end of the movable shaft 236 is connected to and rotates around the axis of the first passive gear 224. By the same token, anyone who is familiar with the technology of the invention will understand that the other end of first shaft 242, the second shaft 244 and the third shaft 246 can be connected to a sporting structure in a rotatable way (not shown in FIG. 3). That is to say, the first roller 228 is connected to the first passive gear 224 via the first shaft 242 to synchronize with the driving gear 222 and the first passive gear 224 and rotate along the first or the second direction carrying the document 212 to enter or leave the lateral reversing device 220. The second roller 230 is connected to the second passive gear 226 via the second shaft 244 to synchronize with the driving gear 222 and the second passive gear 226. The third roller 232 and the second roller 230 are used to clip the document 212, and the two rollers can rotate synchronously along the first direction to move the document 212 forward.

[0028] The gyration orbit 238, which is installed in the casing 202 and situated beneath the covering panel 208 and the third roller 232, is used for the document 212 to pass through to be overturned. The baffle 234 is installed in the lateral panel 209 with a position higher than the infra-margin of the second roller 230 and the entrance of the gyration orbit 238 as well, guiding the document 212 to be fed into the gyration orbit 238. The infrared emitter 240 a and infrared receiver 240 b are installed around the two sides of the exit of the gyration orbit 238, wherein the exit of the gyration orbit 238 is situated on the covering panel 208 lying between the first roller 228 and the second roller 230. In other words, the entrance and exit of the gyration orbit 238 are two openings of the covering panel 208.

[0029] Please refer to FIG. 4, a block diagram according to the scanner as shown in FIG. 2. In FIG. 4, the lateral reversing device 220 is equipped with a control unit 252 which is coupled to the driving gear 222, the movable shaft 236, the carriage 214, the infrared emitter 240 a and the infrared receiver 240 b. The control unit 252 controls the infrared emitter 240 a transmitting infrared to the infrared receiver 240 b. When the infrared is blocked by something in the gyration orbit 238 and the infrared receiver 240 b is unable to receive the infrared emitted by the infrared emitter 240 a, the infrared receiver 240 b will transmit an interrupted signal to the control unit 252. On receiving the interrupted signal, the control unit 252 controls the driving gear 222 to change its rotation direction accordingly. That is to say, on receiving the scan-finished signal or the interrupted signal, the control unit 252 controls the driving gear 222 to rotate in the first or the second direction accordingly; moreover, the first passive gear 224 gears into or detach from the driving gear 222 when the control unit 252 receives the scan-finished signal or the interrupted signal.

[0030] The processes regarding how the lateral reversing device 220 according to the invention overturns the document are explained below. Please refer to FIG. 2, the user can select single-sided scanning module or double-sided scanning module using the operation interface of the scanner 200 (not shown in FIG. 2) before the document 212 is loaded and scanned. When the double-sided scanning module is selected and the carriage 214, after having scanned the document front side 212 a, will transmit a scan-finished signal to the control unit 252. After receiving the scan-finished signal, the control unit 252 will control the movable shaft 236 to move towards the driving gear 222 so that the first passive gear 224 can gear into the driving gear 222 while the document 212 is held by the first roller 228 from above and an edge of the scanning platform 210 from underneath. Meanwhile, the carriage 214 starts to return to the scan-starting position.

[0031] After that, the control unit 252 controls the driving gear 222 to rotate in the first direction. The driving gear 222 will carry the first passive gear 234, the second passive gear 226, the first roller 228 and the second roller to rotate in the first direction synchronously as shown in FIG. 5. The second contact roller 230 will carry the third contact roller 230 to rotate, while the first roller 228 will carry the document 212 to move towards the second roller 230.

[0032] The document 212, having been held by the second roller 230 and the third roller 232 from above and underneath the document 212, will move towards the baffle 234 along with the rotation of the second roller 230 and the third roller 232. The control unit 252 according to the invention can be designed to move the movable shaft 236 away from the driving gear 222 after its rotation has lasted for a period of time so that the first passive gear 224 detaches from the driving gear 222 and the first roller 228 keeps away from the edge of the scanning platform 210. It is noteworthy that after the driving gear 222 has rotated for a period of time, the second roller 230 and the third roller 232 must be able to hold the document 212 form above and underneath and rotate synchronously to carry the document 212 moving forwards, so that the first passive gear 224 can be detached from the driving gear 222. However, the above detachment should not influence the rotation of the driving gear 222.

[0033] Following that, the document 212 will be guided by the baffle 234 to enter the gyration orbit 238 via the entrance of the gyration orbit 238 as shown in FIG. 7. When the document 212 moves to the gyration orbit 238 and blocks the infrared emitted by the infrared emitter 240 a, the infrared receiver 240 b will not be able to receive the infrared emitted by the infrared emitter 240 a. At this moment, the infrared receiver 240 b will transmit an interrupted signal to the control unit 252. After the control unit 252 has received the interrupted signal for a period of time, the second roller 230 and the third roller 232 would have just carried the document 212 to show its front edge above the covering panel 208 via the exit of the gyration orbit 238 with the front edge of the document 212 being placed between the first roller 228 and an edge of the scanning platform 210. The control unit 252 will control the movable shaft 236 to move towards the driving gear 222 so that the first passive gear 224 can gear into the driving gear 222 while the document 212 is held by the first roller 228 from above and an edge of the scanning platform 210 from underneath.

[0034] Then, the control unit 252 will control the driving gear 222 to rotate in a second direction opposite to the first direction. The driving gear 222 will carry the first passive gear 224, the second passive gear 226, the first roller 228 and the second roller rotating synchronously in the second direction. The second contact roller 228 will carry the third contact roller 230 to rotate, while the first roller 228 will carry the document 212 moving towards the scanning platform 210.

[0035] The document 212 would have returned to the scanning platform 210 with the document reverse side 212 b facing downward a little while after the document 212 left the gyration orbit 238 and the infrared receiver 240 b once again received the infrared emitted by the infrared emitter 240 a. In the meanwhile, the carriage 214 would have returned to the scan-starting position as well. The control unit 252 will control the driving gear 222 to stop and the movable shaft 238 to move away from the driving gear 222, so that the first passive gear 224 detaches from the driving gear 222 and the first roller 228 stays away from the scanning platform 210 as shown in FIG. 8. Moreover, the control unit 252 according to the invention can be designed to halt the driving gear 222 a longer after the interrupted signal has been received, so that the document 212 would have just arrived at the scanning platform 210. Following that, the carriage 214 will move in a direction parallel to the second shaft 244 and the third shaft 246 and start to scan the document reverse side 212 b. Since the following scanning processes are the same, they are simply omitted here.

[0036] According to the above explanations, the invention provides a document double-sided scanning method as shown in FIG. 9. In FIG. 9, first of all, the carriage scans the front side of the document from the scan-starting position in step 902. Next, proceed to step 904 where the carriage outputs a scan-finished signal after having scanned the front side of the document and starts to return to the scan-starting position accordingly. Following that, proceed to step 906. The control unit of the lateral reversing device, having received the scan-finished signal, enables a document to be fed into the lateral reversing device from the near side of the scanning platform. After that, proceed to step 908 where the lateral reversing device overturns the document. Then proceed to step 910 where the lateral reversing device returns the document to the scanning platform and the carriage has returned to the scan-starting position. Finally, proceed to step 912 where the carriage starts to scan the reverse side of the document from the scan-starting position and ends the method.

[0037] Anyone who is familiar with the technology of the invention will understand that its application is not limited thereto. For example, the infrared emitter and infrared receiver can be replaced by other sensing units which produce the same sensing effect. Besides, the movable shaft which connects the first passive gear and the third shaft can be replaced by other movable mechanisms or belt sets to move the first passive gear. Furthermore, the first shaft, the second shaft and the third shaft can be equipped with a number of rollers to further improve document holding and document carrying effect. The lateral reversing device according to the invention can be further equipped with a casing to protect the inside parts. An automatic document feeder(ADF), which peers with the lateral reversing device according to the invention, can be installed at the other side of the covering panel of the scanning platform facilitating the user to feed the document into the scanning platform.

[0038] It is noteworthy that the radius of the driving gear must be larger than that of the first and the second passive gears. The invention also allows the driving gear to be omitted, so that the control unit can directly control the rotation of the first and the second gears without using the driving gear as a rotating medium. Moreover, the gyration orbit according to the invention can be replaced by another gyration orbit bypassing the upper-margin of the second roller producing the same effect of document overturning.

[0039] If the infrared emitter and infrared receiver or other sensing units according to the invention are to be omitted, a number of timing which control the rotation of the driving gear as well as the gearing and detachment between the first passive gear and the driving gear need to be designed to assure the desired effect of document overturning.

[0040] Considering the time flow, first of all, the control unit moves the movable shaft away from the driving gear after the driving gear has started rotation for a first period of time, so that the first passive gear detaches from the driving gear and the first roller stays away from the scanning platform. During the mean while, the second roller and the third roller must be able to hold the document from both above and underneath and rotate synchronously to carry the document moving forward.

[0041] Following that, after the driving gear has rotated in a first direction for a second period of time longer than the first period of time, the control unit will move the movable shaft towards the driving gear so that the first passive gear can gear into the driving gear while the document is held by the first roller from above and the scanning platform from underneath. Meanwhile, the front edge of the document has already left the gyration orbit, and the control unit will control the driving gear to rotate in a second direction.

[0042] At last, after the driving gear has rotated in the second direction for a third period of time, the control unit will halt the driving gear while the document would just have returned to the scanning platform.

[0043] A scanner with a lateral reversing device is disclosed in the above preferred embodiments according to the invention. The design of installing a reversing device at a lateral side of the scanning platform enables the scanner to overturn the document after the front side has been scanned so the reverse side can be scanned, achieving a double-sided scanning function. The user does not have to turn the document over manually which is indeed very convenient.

[0044] While the invention has been described by ways of examples and in terms of preferred embodiments, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures. 

What is claimed is:
 1. A scanner, comprising at least: a casing with a covering panel; a scanning platform installed on the covering panel and used to accommodate at least one document; a carriage which is movably installed in the casing and is used to output a scan-finished signal after having scanned the front side of the document; and a lateral reversing device situated at a lateral side of the scanning platform and equipped with a control unit, wherein the lateral reversing device is used to overturn the document for its reverse side to be scanned after the scan-finished signal has been received by the control unit.
 2. The scanner according to claim 1, wherein the lateral reversing device further comprises: a driving gear installed on the covering panel and is situated at an edge of the scanning platform, wherein the driving gear is controlled by the control unit and rotates in a first or a second direction when the control unit receives a scan-finished signal or an interrupted signal; a first passive gear installed on top of the covering panel near an edge of the scanning platform in a movable and rotatable way, wherein the first passive gear gears into or detaches from the driving gear when the control unit receives the scan-finished signal or the interrupted signal; a second passive gear installed on top of the covering panel near a lateral panel of the casing, wherein the second passive gear is used to gear into the driving gear; a first roller connected to the first passive gear via a first shaft, wherein the first roller rotates in the first direction or the second direction along with the driving gear and the first passive gear synchronously carrying the document to enter or leave the lateral reversing device; a second roller connected to the second passive gear via a second shaft, wherein the second roller rotates synchronously with the driving gear and the second passive gear; a third roller, which is installed on the covering panel and makes contact with the second roller high and low, holding the document together with th second roller from above and underneath rotating in the first direction synchronously carrying the document moving forward; a gyration orbit, which is installed in the casing and is situated on top of the second roller or at the underneath of the third roller for the document to pass through and to be overturned; a baffle, which is installed in the lateral panel and situated at the outer side of the entrance of the gyration orbit, guiding the document to be fed into the gyration orbit; and a sensing unit, which is installed near the exit of the gyration orbit, detecting the document and transmitting the interrupted signal to the control unit accordingly so that the control unit controls the driving gear to rotate in the second direction.
 3. The scanner according to claim 2, wherein the lateral reversing device further comprises: a movable shaft or a belt set, wherein one end of the movable shaft or the belt set is connected to the third roller via a third shaft, while the another end of the movable shaft or the belt set is connected to the first passive gear and is controlled by the control unit to get close to or move away from the driving gear so that the first passive gear can gear into or detach from the driving gear.
 4. The scanner according to claim 3, wherein the exit of the gyration orbit is situated at the covering panel lying between the first roller and the second roller.
 5. The scanner according to claim 4, wherein the control unit controls the movable shaft or the belt set to stay away from the driving gear after the driving gear has rotated in the first direction for a period of time, so that the first passive gear detaches from the driving gear with the first roller being away from the scanning platform.
 6. The scanner according to claim 5, wherein the control unit controls the movable shaft or the belt set to move towards the driving gear after having received the interrupted signal for a period of time, so that the first passive gear gears into the driving gear with the document being held by the first roller from above and an edge of the scanning platform from underneath.
 7. The scanner according to claim 6, wherein the control unit halts the driving gear after the sensing unit has received the interrupted signal for another period of time, so that the document would just have arrived at the scanning platform.
 8. The scanner according to claim 6, wherein the sensing unit comprises: an infrared emitter, which is installed at one side of the exit of the gyration orbit, emitting an infrared under the control of the control unit; and an infrared receiver, which is installed at the other side of the exit of the gyration orbit, transmitting the interrupted signal to the control unit when the infrared is not received.
 9. A document double-sided scanning method applied to a scanner, wherein the scanner comprises a carriage, a scanning platform where at least one document is placed, and a lateral reversing device which is installed at a lateral side of the scanning platform, wherein the method comprises: the carriage scans the front side of the document; the lateral reversing device overturns the document after the carriage has scanned the front side of the document; and the carriage scans the reverse side of the document.
 10. The method according to claim 9, wherein the method further comprises: the carriage scans the front side of the document from a scan-starting position; the carriage outputs a scan-finished signal after having scanned the front side of the document and starts to return to the scan-starting position; a control unit of the lateral reversing device, having received the scan-finished signal, enables the document to be fed into the lateral reversing device from the near side of the scanning platform; the lateral reversing device overturns the document; the lateral reversing device returns the document to the scanning platform and the carriage has returned to the scan-starting position; and the carriage starts to scan the reverse side of the document from the scan-starting position. 